Discovering the Were-plant!
By zteve t evans
A rather unremarkable and scruffy looking plant studied by two scientists has been dubbed the were-plant after it was discovered that it only pollinates during the light of the full moon in June. A study Moonlight pollination in the gymnosperm Ephedra (Gnetales) undertaken by Catarina Rydin , Kristina Bolinder, Published, 1 April, 2015, looked at how Ephedra (Gnetales) reproduced and in doing so made a remarkable discovery. The study is the result of four seasons of field studies so far which show a surprise relationship between pollination of one of the study species of plants with the lunar cycle in one of the species that they were studying. This work looks at how the discovery was made and what problems the researchers see for the future of the plant.
Cycles of the moon
The cycles of the moon are are used by a many animals for a number of reasons such as navigation and communication. Now researchers have discovered the first known case of a plant that times its reproduction to the cycles of the moon. The plant is a rather modest shrub found in areas around the Mediterranean and is known as Ephedra foeminea though since the discovery of its connection to the moon it has been nick-named the were-plant. This is because the plant is a non-flowering relative of conifers and instead of flowers produces masses of red and yellow cones which during the full moon in July secretes sugary fluid to attract the nocturnal insects which pollinate it.
Sole survivor
The researchers think it may be the sole surviving species of a pollination system that was once widespread according to the report published by The Royal Society, Biology Letters by Catarina Rydin and Kristina Bolinder of the University of Stockholm. They think the insects are attracted by the reflections of moonlight in the globules of the liquid the plants secrete and was only discovered by chance. Dr Catarina Rydin said, “After a useless week in Greece without any pollinators to observe, we were in a really bad mood and decided not to go to the field sites that night but to go to dinner instead. All of a sudden we experienced a eureka moment, perhaps from seeing the moon on photos from a previous year, and contrasting it with the darkness we’d experienced so far at the field site.”
An unattractive plant in daylight
Ephedra foeminea grows on bare rocky areas, ravines and cliffs in areas of the eastern Mediterranean region. It is a gymnosperm having reproductive parts inside cones like pine trees. Some of these rely on the wind to spread pollen while others make pollen drops to attract insects, flies and moths to aid pollination.
In the bright light of day the shrub is not a particularly attractive one. One of the researchers, botanist Catarina Rydin, of the University of Stockholm says of the plant, “Ephedra foeminea is a big, scrambling shrub, rather ugly in fact,” that clings to rocks around the eastern Mediterranean. It does have leaves but they are very small and so people call it the leafless Ephedra. However, when it is time for it to reproduce it behaves like a sort of were-plant producing masses of brightly colored red and yellow cones to coincide with the full moon in July.
Insect pollination
The relatives of Ephedra were around with the dinosaurs around 130 million years ago during the Early Cretaceous Period. Instead of producing flowers to aid reproduction it produces cones which secrete liquid containing pollen. Although some species of the plant use the wind to carry drops between cone the liquid is very sugary and insects are attracted to it. From studies of the fossil record Rydin thinks Ephedra survived extinction by evolving from relying on the wind to spread its pollen to a become an insect pollinated plant.
Rydin says, "Historically, climate change has occurred repeatedly, not least in the aftermath of the meteorite impact 65 million years ago, and wind-pollination may have been a safer method to ensure reproduction during such times," and adds,"It is thus possible that insect-pollinated species of Ephedra had a greater risk of becoming extinct."
The cycles of the moon are are used by a many animals for a number of reasons such as navigation and communication. Now researchers have discovered the first known case of a plant that times its reproduction to the cycles of the moon. The plant is a rather modest shrub found in areas around the Mediterranean and is known as Ephedra foeminea though since the discovery of its connection to the moon it has been nick-named the were-plant. This is because the plant is a non-flowering relative of conifers and instead of flowers produces masses of red and yellow cones which during the full moon in July secretes sugary fluid to attract the nocturnal insects which pollinate it.
Sole survivor
The researchers think it may be the sole surviving species of a pollination system that was once widespread according to the report published by The Royal Society, Biology Letters by Catarina Rydin and Kristina Bolinder of the University of Stockholm. They think the insects are attracted by the reflections of moonlight in the globules of the liquid the plants secrete and was only discovered by chance. Dr Catarina Rydin said, “After a useless week in Greece without any pollinators to observe, we were in a really bad mood and decided not to go to the field sites that night but to go to dinner instead. All of a sudden we experienced a eureka moment, perhaps from seeing the moon on photos from a previous year, and contrasting it with the darkness we’d experienced so far at the field site.”
An unattractive plant in daylight
Ephedra foeminea grows on bare rocky areas, ravines and cliffs in areas of the eastern Mediterranean region. It is a gymnosperm having reproductive parts inside cones like pine trees. Some of these rely on the wind to spread pollen while others make pollen drops to attract insects, flies and moths to aid pollination.
In the bright light of day the shrub is not a particularly attractive one. One of the researchers, botanist Catarina Rydin, of the University of Stockholm says of the plant, “Ephedra foeminea is a big, scrambling shrub, rather ugly in fact,” that clings to rocks around the eastern Mediterranean. It does have leaves but they are very small and so people call it the leafless Ephedra. However, when it is time for it to reproduce it behaves like a sort of were-plant producing masses of brightly colored red and yellow cones to coincide with the full moon in July.
Insect pollination
The relatives of Ephedra were around with the dinosaurs around 130 million years ago during the Early Cretaceous Period. Instead of producing flowers to aid reproduction it produces cones which secrete liquid containing pollen. Although some species of the plant use the wind to carry drops between cone the liquid is very sugary and insects are attracted to it. From studies of the fossil record Rydin thinks Ephedra survived extinction by evolving from relying on the wind to spread its pollen to a become an insect pollinated plant.
Rydin says, "Historically, climate change has occurred repeatedly, not least in the aftermath of the meteorite impact 65 million years ago, and wind-pollination may have been a safer method to ensure reproduction during such times," and adds,"It is thus possible that insect-pollinated species of Ephedra had a greater risk of becoming extinct."
How does E. foeminea pollinate?
They knew that one of its close relatives, E. distachya, spread its pollen using the wind as other researchers of the species have verified, but no one was certain how E. foeminea pollinated. Mysteriously even when its cones had grown they simply did not open to release pollen and usual insect pollinators seemed to show no interest in them.
Discussing the baffling problem of pollination over dinner one night the the idea the plant was connected to the lunar cycle was mentioned as a joke. They had been discussing how insects used the moon to navigate, as dedicated scientists will over dinner! But thinking about it further they realized it was a possibility and decided to investigate further and researched nocturnal pollination.
The night of the full moon
On the night of the full moon in July they situated themselves amid an area of E. foeminea and waited. As the moon rose its light caught the drops of pollen on the plant causing them to glitter and sparkle on the bright red and yellow cones giving them a beauty that was not apparent in daylight. Rydin said, "We may be biased, but we found it ever so beautiful.”
Puzzlingly, most plants that bloom at night have white flowers and give out a scent which aids pollinators to find them in the dark, but E. foeminea has yellow and red cones which do not give out any discernible odor to attract pollinators. Rydin says, “It became clear to us that the glittering probably is the means of nocturnal attraction that we had searched for but not found before,” The light of the full moon caused the drops of liquid on the cones to shimmer and glitter which the researchers believe attracted the insects, flies and moths that settled on the cones. As the pollinators moved from cone to cone by the light of the moon the pollen was spread.
The researchers think that although the light from a half moon would possibly be enough to catch in the pollen causing it to sparkle they think that because the full moon remains at its peak throughout the night the plant has evolved to take advantage of this opportunity. Rydin says, “Only at full moon do the insects have a moon to navigate by during the entire night,”
The spectacular display of glittering pollen has only been seen once but the researchers have historical data that appears to give weight to their observations. They noted that while the plant did produce pollen drops at the times of the full moon in August and September there was considerably less cones on show. This led the researchers to think that the plant peaks in the summer months like its relatives do.
Questions that remain
There are still many unanswered questions. For example, how does E. foeminea time its cone and pollen production to peak at the time of the full moon in summer? The researchers think that as the plant is sensitive enough to react to the moonlight and are thought to be able to " sense" gravitational changes in the tidal pull of the moon.
Concerns for the future
The researchers raised concerns that as E. foeminea depends on moonlight to reproduce whether growing light pollution from human settlements would have an adverse effect. They also raise concerns about climate change causing more clouds to appear in the normally clear summer night skies where it grows adversely affecting its ability to reproduce.
© 22/05/2015 zteve t evans
They knew that one of its close relatives, E. distachya, spread its pollen using the wind as other researchers of the species have verified, but no one was certain how E. foeminea pollinated. Mysteriously even when its cones had grown they simply did not open to release pollen and usual insect pollinators seemed to show no interest in them.
Discussing the baffling problem of pollination over dinner one night the the idea the plant was connected to the lunar cycle was mentioned as a joke. They had been discussing how insects used the moon to navigate, as dedicated scientists will over dinner! But thinking about it further they realized it was a possibility and decided to investigate further and researched nocturnal pollination.
The night of the full moon
On the night of the full moon in July they situated themselves amid an area of E. foeminea and waited. As the moon rose its light caught the drops of pollen on the plant causing them to glitter and sparkle on the bright red and yellow cones giving them a beauty that was not apparent in daylight. Rydin said, "We may be biased, but we found it ever so beautiful.”
Puzzlingly, most plants that bloom at night have white flowers and give out a scent which aids pollinators to find them in the dark, but E. foeminea has yellow and red cones which do not give out any discernible odor to attract pollinators. Rydin says, “It became clear to us that the glittering probably is the means of nocturnal attraction that we had searched for but not found before,” The light of the full moon caused the drops of liquid on the cones to shimmer and glitter which the researchers believe attracted the insects, flies and moths that settled on the cones. As the pollinators moved from cone to cone by the light of the moon the pollen was spread.
The researchers think that although the light from a half moon would possibly be enough to catch in the pollen causing it to sparkle they think that because the full moon remains at its peak throughout the night the plant has evolved to take advantage of this opportunity. Rydin says, “Only at full moon do the insects have a moon to navigate by during the entire night,”
The spectacular display of glittering pollen has only been seen once but the researchers have historical data that appears to give weight to their observations. They noted that while the plant did produce pollen drops at the times of the full moon in August and September there was considerably less cones on show. This led the researchers to think that the plant peaks in the summer months like its relatives do.
Questions that remain
There are still many unanswered questions. For example, how does E. foeminea time its cone and pollen production to peak at the time of the full moon in summer? The researchers think that as the plant is sensitive enough to react to the moonlight and are thought to be able to " sense" gravitational changes in the tidal pull of the moon.
Concerns for the future
The researchers raised concerns that as E. foeminea depends on moonlight to reproduce whether growing light pollution from human settlements would have an adverse effect. They also raise concerns about climate change causing more clouds to appear in the normally clear summer night skies where it grows adversely affecting its ability to reproduce.
© 22/05/2015 zteve t evans
Reference and Attributions
Copyright 22nd May, 2015 zteve t evans
Copyright 22nd May, 2015 zteve t evans
- "Wereplant" Releases Its Pollen By the Light of the Full Moon - Smithsonian
- File:Ephedra foeminea 1.jpg From Wikimedia Commons - Gideon Pisanty (Gidip) - CC BY 3.0
- File:Ephedra foeminea 2.jpg From Wikimedia Commons - Ephedra foeminea, - Author Franz Xaver - Creative Commons Attribution-Share Alike 3.0 Unported license.
- Moonlight pollination in the gymnosperm Ephedra (GnetalesEphedra foeminiea - The IUCN Red List of Threatened Species